Refrigerating apparatus



Filed Jam.4 l1, 1935 Patented Nov. 12, .1935

ITE STATES PATENT OFFiCE nnraronas'rrnc. firmamos MApplication January l1, 1935, Serial No. 1,3% s claims. (ci. (i2-ns) This invention relates to improvements in 're frigerating apparatus and, more especially, a construction with means to prevent undesirable frosting of the refrigerant supply pipe leading 5 from a float valve, expansion valve, capillary tube, or the like to the evaporator.

In many conventional types of refrigerators at present on the market, the evaporator isl placed inside of the cooling compartment where space is somewhat limited. The compressor, condenser and other mechanical equipment are ordinarily placed in a separate compartment. This may be referred to for convenience as the machine compartment. In such a construction, it

is necessary to lead the supply pipe from the machine compartment to the evaporator in the cooling compartment. It is well known that in conventional refrigerating apparatus using a compressor, condenser and evaporator there must be a control valve of some sort, or its equivalent, to control the flow of refrigerant from the condenser to the evaporator. This control valve, for example, may be in the form of a float valve, expansion valve, or even a capillary tube. For

the purpose of illustrating this invention, I shall consider the control valve in general as in the form of a float valve.

In some constructions, the float valve is placed svery close to or even inside of the evaporator. In

such constructions, there is very little, if any,

exposed pipe lea-ding from the float valve to the evaporator and, consequently, practically no problem is presented of undesirable frosting on such supply pipe. Since the space in the cooling compartment is often limited, it may be impractical or undesirable to place the float valve close to or inside of the evaporator. If this is done, the evaporator may have to be unduly enlarged or valuable space in the cooling compartment is taken up by the fioat valve. Also, because of temperature conditions, space requirements and mechanical and other requirements, it may be impractical or undesirable to place the float valve close to' or inside of the ev-aporator. If-the float valve is not so placed, the only other convenient and practical location for it ordinarily is in the machine compartment. When so placed, however, there must necessarily extend a supply pipe from the float valve in the machine compartment to the evaporator in the cooling-compartment. Since this pipe lies on the evaporator side of the control valve, it will become cold and undesirable or objectionable frost will accumulate upon it unless means are provided to prevent such frosting. The principal feature of this invention-is theprovision of means to prevent such frosting on thesupply pipe.

In general, it may be stated that such objectionable frosting is prevented by insulating the supply pipe. This insulating is accomplished by running the supply pipe inside of the return pipe, the latter thereby serving as an insulator. Means are provided to space the supply pipe from the inner walls of the return pipe, as will be described in detail hereinafter.

In some constructions heretofore known where the control valve is located some distance from the evaporator, a-loaded valve has been placed between the supply pipe and the evaporator, said valve adapted to open when the pressure of the 15 liquid refrigerant in the supply pipe exceeds a predetermined value. .This construction is illustrated, for example, in Peltier patent, No. 1,891,- 357, of December 20, 1932. Such a valve is designed to maintain the liquid in the supply pipe at such a pressure that evapor-ation will not take place; and this is designed to prevent objectionable frosting onv the supply pipe. My improved construction shows another means for preventing such objectionable frosting without necessitating 25 the use of such a loaded valve. Such a valve is expensive and presents questions of maintenance and repair. My improved means for preventing frosting is designed to overcome all the problems spoken of in the Peltier patent and will per- 30 form" all the functions claimed for the loaded valve in such patent; and my improved means has no moving parts and can be easily and' cheaply constructed.

In that form of device embodying the femmmes-tg..` Y

of my invention shown in the accompanying drawing:- i

Figure 1 is a diagrammatic view; Fig. 2 is an enlarged view taken as indicated by the line 2 of Fig. l; Fig. 3 is a view of the spacing wire 4.0 on an enlarged scale; and Fig. 4 is a View taken as indicated by the line 4 of Fig. l.

. As shown in the drawing, there is indicated diagrammatically in Fig. 1 a complete refrigerating circuit, including the compressor lll, condenser |.I, float valve or refrigerant flow control means I2 and evaporator or refrigerator element I3. I4 indicates the supply pipe or conduit leading from the float valve to the evaporator and I5, the return pipe leading from. the evaporator to the compressor.

As here shown, the return pipe I5 has an enlarged section I5a in the form of a pipe of larger diameter with circular end closure membersl, IB. The supply pipe I4 has an external diameter 55 pipe' I5a so that the latter virtually forms a pa'rt of the return pipe itself. That is, the refrigerant in thereturn circuit enters'the pipe I5a at one end from the evaporator, flows through the pipe |52- around the supply pipe I4 and then leaves the pipe I5a through the other pipe I5 leading to the compressor I Il.

By this construction, it will be seen that the pipe I4 is insulated by the return pipe I5a with the return flowing refrigerant therein. Thereturning refrigerant is warm enough to prevent frosting on the pipe |55.

Means are provided for centering the pipe I4 inside of the`pipe AI5fi. This includes a coil of wire 20, as shown in Fig. 3, the separate convolutions`being triangular. This coil is wound around the pipe I4 when it is slipped into the pipe I5a and holds the pipe in concentric relationship with proper spacing between the same, as shown in Fig. 2.

As has been stated, the return pipe with the returning refrigerant therein insulates the supply pipe I4 to prevent undesirable frosting. The term insulate may not be used correctly in a highly technical sense, since it will be noticed that there is some heat exchange between the vpipe I4 and the returning refrigerant in the pipe I5, In many cases, however, it is believed that the temperature of the returning refrigerant will v be lower than the temperature of the surrounding air to which the pipe I4 would be exposed if in the apparatus; and furthermore will prevent 1 the objectionable frosting that otherwise would occur.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modications. Changes, therefore, inV the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed i in the appended claims, in which it is my intention to claim all novelty inherent in my invention as broadly as permissible, in view of the prior art. f

What I claim as new, and desire to secure by Letters Patent, is: A

1. In a retrigerating system of the compressorcondenser-evaporator type, the combination of a refrgerating element, a supply conduit for supplying liquid refrigerant to said element, means for supplyingliquid refrigerant to said supply conduit, refrigerant` flow control means between 5 o the supply conduit lies inside of the return con- 15 duit, and in which means are provided for spacing the supply conduit from the return conduit.

4. Apparatus as claimed inclaim 1, in which the supply conduit lies inside of the return'conduit and in which means are provided for spac- 20 ing the supply conduit from the return conduit, said means including a wire wound around the supply conduit.

5,. Apparatus as claimed in claim 1,in which the supply conduit lies inside of the return con- 25 duit and in which means are proided for spacing the supply conduit from the return conduit, said means including a wire of polygonal form would wound around the supply conduit.

6. In a refrigerating system of the compressor-4 30 condenser-evaporator type,the combination of a refrigerating element, a supply conduit for supplying liquid refrigerant to said element, means for supplying liquid refrigerant to said supply conduit, refrigerant flow control means between 35- said means and said supply conduit, a return conduit for returning refrigerant from the refrigerating element, said return conduit. having a portion of its length lying inside of said enlarged section of said return conduit.

7. In a refrigerating system of the compressorcondenser-evaporator type with flow control means located a considerable distance from the evaporator and a supply pipe connecting said ow control means and said evaporator; a re- 45' frigerant return pipe leading from the evaporerant return pipe leading from the evaporator, 5,5 y

with at least a portion of the supply pipe and a portion of the return pipe lying in such close relationship that objectionable frosting on said portion of said'supply pipe is prevented.

JENs TOUBORG. 6 

